The FDA granted fast track designation to TT-00420, a FGFR spectrum selective kinase inhibitor, for the potential treatment of patients with cholangiocarcinoma with no standard treatment options, according to a press release. 

The FDA based the designation on findings from a phase 1 study. Nine patients were given different doses of TT-00420, with seven undergoing at least one assessment after the treatment. Four patients achieved partial response, while 5 achieved stable disease. One patient who achieved partial response maintained that status for around 10 months. 

The release noted that 5 patients in the trial had FGFR2 fusion or rearrangement and had resistance to prior FGFR inhibitors. One of the patients with primary resistance achieved a partial response with a progression-free survival of around 8 months. 

“The clinical evidence supports the continuing exploration of TT-00420 in treating cholangiocarcinoma patients with no standard treatment options,” the release said. 

The FDA previously granted TT-00420 orphan drug designation to treat cholangiocarcinoma.